/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.apache.mxnet.spark

import org.apache.mxnet.NDArray

/**
 * A wrapper for serialize & deserialize ``org.apache.mxnet.NDArray`` in spark job
 * @author Yizhi Liu
 */
class MXNDArray(@transient private var ndArray: NDArray) extends Serializable {
  require(ndArray != null, "Undefined ndArray")
  private val arrayBytes: Array[Byte] = ndArray.serialize()

  def get: NDArray = {
    if (ndArray == null) {
      ndArray = NDArray.deserialize(arrayBytes)
    }
    ndArray
  }
}

object MXNDArray {
  def apply(ndArray: NDArray): MXNDArray = new MXNDArray(ndArray)
}
